<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        .test{
            display: flex;
            justify-content: space-between;
        }
        .container{
            width: 300px;
        }
    </style>
</head>
<body>
    
    <div>
        <button class="btn">按钮</button>
    </div>
    <div class="practice-container">


    </div>

    <script src="DOM1.js"></script>
</body>
</html>
